1. Field of the Invention
Aspects of the present invention relate to an image forming apparatus for and a method of properly setting a gray level of print data, and more particularly, to setting print density according to the demand of a user.
2. Related Art
An electro-photographic image forming apparatus transforms color coordinates of color component data RGB of an input image into CMYK print data and provides the print data to a printer engine so as to print a corresponding image. The image may be scanned by a scanner or received from a host computer. Although the electro-photographic image forming apparatus should print an image identical to the original image, as a result of differences in printer types, the printed image may have different colors due to characteristics of hardware, print sheets, and developer agents.
Korean Patent Unexamined Application Publication Nos. 2002-41697 and 2006-32677 disclose methods of using a color profile in order to compensate for the difference in color. According to the method in the 2002-41697 reference, a source color table as a reference of colors in a computer is outputted to a printer, and a color chart outputted to the printer is scanned by a scanner to create an output color table. Errors between the source color table and the output color table are extracted and stored in a printer compensation color table. The error values of the printer compensation color table are applied to a corresponding color value when outputting an actual image so as to compensate for the errors. The method in the 2006-32677 reference estimates an error of image data corresponding to a print color chart printed by image data corresponding to a reference color chart and a print color table to which a color profile is applied, and modifies the color profile such that the print colors are changed into the reference colors based on the estimated error.
Generally, when color component data is converted into the print data, the colors are compensated and a gray level is set using a conversion table. However, a gray level that determines brightness of a printed image may not be set properly due to various factors. These factors include ambient temperature and humidity of the apparatus, age of the apparatus, and apparatus type. The references described above do not disclose setting the gray level. If the gray level is not set properly, image reproducing quality in relation to the brightness may be reduced.
Demand exists to reproduce a source image accurately as well as to allow a user to adjust the print density of the printed image. Since the conventional method does not enable the user to adjust the print density of the apparatus, the user's desire to change the print density of the printed image cannot be accommodated.